I don't know. I'm either not paying attention, jaded, or I've just never found people to be more rude in general nowadays compared to earlier in my life, regardless of the places I've lived in. I find it nice that people would respond at all. In fact, I like it when people say "no problem." Most of the time they say it with a smile, anyway, which is always nice.

And what's wrong with hearing "have a good one" or "you bet"? Maybe it's a local/cultural thing? Maybe we're just looking for alternate ways to say please and thank you as to not sound redundant, or even old-fashioned.

I'm just glad at all that we still smile and generally won't let kind gestures go unacknowledged.